I hope I don't cause a problem posting this in here. (Maybe a sticky could be made on how to upload pictures in the other way).
I often see alot of people saying how uploading their pictures in this way makes them "appear" small. That's because it's an attatchment, people are then meant to click on it to then view the full size.

A way to get the picture to show up full size without anyone having to click on it is by using a site like Image hosting, free photo sharing & video sharing at Photobucket. Then copying the IMG codes into your post.